This guide covers the practical basics of working with lyophilized research peptides in the laboratory: what the documentation means, how to store vials, how to choose a diluent and how to keep good records. It is written for researchers and does not describe any use in humans or animals.
What a research peptide is
A peptide is a short chain of amino acids joined by peptide bonds. Most research peptides are between 2 and 50 amino acids long, which places them between single amino acids and full proteins. They are usually made by solid phase peptide synthesis, purified by preparative HPLC and then freeze dried into a stable powder.
Some compounds in our catalog are larger, such as recombinant HGH at 191 amino acids, and a few are not peptides at all, such as NAD+ and 5-Amino-1MQ. Each product page states the compound class so there is no confusion.
How to read a certificate of analysis
A certificate of analysis, or COA, is the record that links a specific batch to its test results. When you review one, check these fields first.
- Batch or lot number. It should match the number on your vial. A COA for a different batch tells you nothing about the material in your hands.
- Identity. Mass spectrometry (MS or LC-MS) confirms the measured molecular weight matches the expected sequence.
- Purity. Reverse phase HPLC reports the share of the main peak against related impurities such as truncated or deleted sequences. Purity is a percentage of peptide content, not of total vial weight.
- Appearance and net content. Most peptides are a white to off white powder. GHK-Cu is blue because of its copper ion.
- Test date and method. A recent date and a named method make the result easier to evaluate and reproduce.
Purity and peptide content are different measures. A vial can show high HPLC purity while also containing counter ions and residual water, which is normal for lyophilized peptides.
Storing lyophilized peptides
Lyophilized peptides are far more stable than peptides in solution, but they still degrade with heat, light and moisture. Follow these practices for sealed vials.
- Store long term at -20 °C. Short periods at 2 to 8 °C are acceptable for most compounds.
- Keep vials in their box or in the dark. Light can degrade residues such as tryptophan.
- Let a cold vial reach room temperature before opening it, so moisture does not condense on the powder.
- Avoid repeated freeze and thaw cycles once a peptide has been reconstituted.
Choosing a reconstitution solution
The right diluent depends on the compound and on how the vial will be used.
| Diluent | Composition | Typical use |
|---|---|---|
| Bacteriostatic water | Sterile water with 0.9% benzyl alcohol | Most peptides, especially when a vial is accessed several times |
| Acetic acid water | 0.6% acetic acid in sterile water | Peptides that dissolve poorly at neutral pH, such as some growth factors |
Add the diluent slowly down the inside wall of the vial rather than directly onto the powder, then swirl gently. Shaking can cause foaming and may damage some peptides. Once dissolved, store solutions refrigerated and protected from light according to your laboratory protocol.
Calculating concentration
Concentration is the amount of peptide divided by the volume of diluent. For example, 10mg of peptide dissolved in 2ml of diluent gives 5mg per ml. Record the batch number, the volume added, the date and the resulting concentration on the vial label and in your lab notebook.
Understanding the research areas
Our catalog is grouped into research areas so related compounds sit together.
- Metabolic research: incretin and amylin analogs, AOD-9604 and NNMT inhibition.
- Tissue research: BPC-157, TB-500, GHK-Cu and KPV.
- Neural research: Semax, Selank, Dihexa, DSIP and bioregulators.
- Cellular research: MOTS-c, NAD+, Epithalon and thymic peptides.
- Endocrine research: GHRH analogs, GH secretagogues, IGF-1 LR3 and gonadotropins.
- Bioregulators: short peptides such as Vilon, Vesugen and Testagen.
- Peptide blends: two or more compounds in one vial.
- Research bundles: multi vial sets at a lower combined price.
- Reconstitution supplies: bacteriostatic water and acetic acid water.
Research use and compliance
All products are sold for in vitro and preclinical research only. They are not approved for any human or veterinary use. Researchers are responsible for following the regulations of their country and the policies of their institution, including any rules on controlled or restricted compounds.